Sanding Birch Plywood floors: Orbital or Belt?

Hi...I'm just about to finish my new birch plywood floors. I have been spot sanding some spots, and the wood filler, but I need to rent a floor sander to finish the whole thing. I'm worried that a belt sander might tear the plywood up a little bit...but I could be wrong. So..I need to decide (in the next 24 hours) which to use. any suggestions?

Thanks,

Mike in Boulder

Yikes, the surface ply on most birch plywood is paper thin. A belt-type floor sander will expose the adhesive and part of the next layer! Those things can gouge. I've never used a walk-behind orbital, so I wouldn't know whether its safe. When making cabinetry, I stick to an orbital palm sander for that stuff.

Good luck!
-KP

Thanks KP. I have an orbital hand sander...but it seems like it would take forever to do a whole floor. I'm leaning towards the orbital though.

Rent a 16 orbital sander with a pad driver attached. Under the buffer you should put a 1 white buffing pad by 3M or Norton followed by a strip of abrasive sandpaper. For this application I typically use 180grit followed by 220. You can source the sandpaper (2 PSA roll) from a local tool supply house. Do not use a small handheld random orbital sander or walk behind belt/drum sander! After sanding the floor apply yours sealer coat then use the same buffer set-up with 220 grit to knock down any raised grain...another coat of finish...buffer w/220...on and on. With a ply floor it is veryimportant to have a very thick film build and recoat often. If you can find it use Bonakemi Traffic 2-part H20 finish or one of the comps.

I can't imagine ply being easy to sand. May I suggest stripper and leave the marks as 'patina'?

I agree with Christof about using a floor buffer. You won't need much grit and they generally don't gouge. Christof is a professional wood floor guy with beautiful work so he's probably the guy to listen to.

Well...thanks for all the suggestions. Today's the day. I'm heading down to get the Traffic now. Man...that stuff is liquid Gold!!! $360 for three gallons!!! I'm heading to Denver to pick it up, and will hopefully get a coat or two on the floor today.

Wish me luck!

Michael

If you did not get the BonaSeal to use with Traffic then you can use neutral stain for your sealer. The waterborne sealer will give a lighter/pale appearance but the neutral stain will give you more depth to the overall look of the grain. If you are using birch plywood, an oil base neutral stain will look stunning with Traffic over top....wait 24 hrs for the stain to dry.

You might be better off trying to coat one plywood panel at a time with Traffic after sealing vs. trying to coat the entire floor at once. Use a wide synthetic staining pad (7-9 ) when applying the Traffic in this manner....read the bottle and follow the directions but you will not need to pour out a 4 wide line like they say, instead use about an inch wide strip. Apply with the grain and try not to work the finish around too much or it can bubble. You will be surprised how nice it goes on but remember you only have a couple hours before your stuck with a $100 bottle of hard finish. Pay no attention to the look of the floor right after you apply H20 finish, it will look horrible at first but as the water evaporates the finish lays down. After your first coat of traffic the plywood will and should feel pretty rough because of the grain raising. You will need to sand the floor with 180 or 220 grit before applying the next coat.

I sent my phone # via e-mail, ring me if you need more help and be sure to take a bunch of pictures so everyone here can follow the process.

Cheers
Christof

Ok folks...I did it! Got the fourth and final coat of Traffic on today, and here are some pics of the results. I will never be mistaken for a professional installer, but I am happy with the results.

It is 3/4 Baltic Birch on a foam pad, screwed into the subfloor. Sanded with 80, then 120. Wood filler between seams and in screw holes. 1 coat of Bona X sealer, then 3 coats of Bona Traffic. Sanded with 220 in between coats, and spot fixed if there were drips and such.

Wow! Nice work,...really!

That looks beautiful! I love the way you layed out the strips of wood. Two fat thumbs up from me!

Dan

LOL... so sorry!! Just sent you a message about YOUR thread, then saw this one in my inbox. I haven't logged into livemodern in too long, it seems!

I haven't started my floor yet, so I wouldn't have been much help - doesn't seem you needed it though, seeing the finished product!!

Rob